Use of a celecoxib composition for fast pain relief

ABSTRACT

There is provided a method of rapidly relieving pain in a mammalian, preferably human, subject. The method comprises orally administering to the subject an effective pain-relieving amount of a composition comprising celecoxib formulated in such a way as to provide, when tested in fasting humans in accordance with standard pharmacokinetic practice, a blood plasma concentration profile of celecoxib in which a concentration of about 250 ng/ml is attained not later than about 30 minutes after oral administration.

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to U.S. Application No.60/207,729 filed May 26, 2000.

FIELD OF THE INVENTION

[0002] The present invention relates to new uses of certain orallydeliverable pharmaceutical formulations containing the selectivecyclooxygenase-2 inhibitory drug celecoxib, for fast relief of pain, andfor manufacture of medicaments useful in treatment of pain.

BACKGROUND OF THE INVENTION

[0003] Numerous compounds have been reported having therapeuticallyand/or prophylactically useful selective cyclooxygenase-2 inhibitoryeffect, and have been disclosed as having utility in treatment orprevention of specific cyclooxygenase-2 mediated disorders or of suchdisorders in general. Among such compounds are a large number ofsubstituted pyrazolyl benzenesulfonamides as reported in U.S. Pat. No.5,760,068 to Talley et al., including for example the compound4-[5-(4-methylphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamide,also referred to herein as celecoxib. Celecoxib has the structure shownin formula (I):

[0004] A need for orally deliverable pharmaceutical compositions givingfast relief of pain exists. A particular need exists for suchcompositions giving fast relief of pain through selective inhibition ofcyclooxygenase-2 (COX-2), without the undesirable side effectsassociated with inhibition of cyclooxygenase-1 (COX-1) that can occurwith conventional non-steroidal anti-inflammatory drugs (NSAIDs). Anespecial need exists for such compositions giving fast relief of painthrough selective inhibition of COX-2, yet exhibiting an onset ofeffective pain relief at least as rapid as standard NSAIDs used in theart, for example ibuprofen.

[0005] Celecoxib is well known as a highly effective selective COX-2inhibitory drug and is widely prescribed for treatment of chronicinflammatory diseases such as rheumatoid arthritis and osteoarthritis.Celecoxib is available under the trademark Celebrex® of PharmaciaCorporation in capsule dosage forms containing 100 mg or 200 mg of thedrug. Although these dosage forms can provide very effective relief ofpain, they can, at least in some acute pain situations, exhibit a sloweronset of pain relief than a standard NSAID such as ibuprofen.

[0006] A suspension of particulate celecoxib in a vehicle of apple juiceis disclosed in Ecuador Patent Application No. 98-2761 (“EC 98-2761”which corresponds to WO 00/32189, Jun. 8, 2000). See in particularExample 13 therein, which describes preparation of such a suspension bydissolving celecoxib in ethanol containing 5% polysorbate 80 and addingthe resulting mixture to apple juice prior to oral administration to 10healthy male subjects. The dose administered was 300 mg celecoxib. Anequal 300 mg dose was administered for comparison, in the form of three100 mg capsules containing formulated celecoxib having a D₉₀ particlesize of about 37 μm (i.e., 90% by weight of celecoxib particles in theformulation were smaller, in their longest dimension, than about 37 μm).Pharmacokinetic parameters disclosed indicate that the suspension gave ahigher C_(max), shorter T_(max) and shorter T_(1/2) than the capsules asindicated in Table 1 below, where C_(max) is the average maximum bloodplasma concentration of celecoxib following administration, T_(max) isthe average length of time from administration until C_(max) is reached,and T_(1/2) is the average terminal half-life of blood plasmaconcentration of celecoxib following T_(max). TABLE 1 Pharmacokineticsof celecoxib suspension and capsule formulations (from Ecuador PatentApplication No. 98-2761) 300 mg celecoxib 300 mg celecoxib as suspensionas capsules C_(max) (ng/ml 1526.5 1076.5 plasma) T_(max) (h) 1.42 1.94T_(1/2) (h) 11.53 15.57

[0007] Ibuprofen in a typical acute pain relief dose of 400 mg normallyprovides an adequate level of suppression of pain, for examplepost-surgical pain, by about 1 hour after administration. Celecoxib incapsule form normally takes longer, for example about 2 hours, toachieve a similar level of pain suppression. No suggestion is made inabove-cited EC 98-2761 that the apparently modest reduction in T_(max)exhibited by the disclosed suspension by comparison with the capsuleformulation, when administered in a 300 mg dose, could be associatedwith a major improvement in onset of pain relief, or that the suspensionformulation of celecoxib could be at least comparable with ibuprofen inonset of pain relief.

[0008] Above-cited EC 98-2761 merely discloses in general terms thatcompositions of the invention disclosed therein, i.e., including thedisclosed capsule formulations as well as the suspension composition ofExample 13 thereof, are effective “for pain management generally(particularly post-oral surgery pain, post-general surgery pain,post-orthopedic surgery pain, and acute flares of osteoarthritis)”.Nevertheless, this reference contains no suggestion that the suspensioncomposition might provide an effective pain relieving amount ofcelecoxib nor was it appreciated by this reference that an effectivepain-relieving concentration of 250 nm/ml plasma or greater could beachieved in a rapidly bioavailable formulation. This is particularly inview of the extensive binding of celecoxib to plasma albumin which wasknown to occur following oral administration (Davies et al., Clin.Pharmacokinet. 38:225-242, 2000). Thus, one could not have predictedthat a particular plasma concentration would produce analgesia.

[0009] Australian Patent Applications No. 200042711, No. 200043730 andNo. 200043736 disclose compositions comprising a selective COX-2inhibitory drug, a 5HT₁ receptor agonist and caffeine, said to be usefulfor treating migraine.

[0010] Although objectives of the present invention are not limited toany particular measure of analgesic response, a method of providinganalgesia with an onset time of 60 minutes or less, especially 30minutes or less and ideally 15 minutes or less, by oral administrationof a celecoxib composition would be an important advance in the art.

SUMMARY OF THE INVENTION

[0011] It has now surprisingly been discovered that celecoxib canprovide acceptable relief of acute pain within about 60 minutes or lessafter oral administration, in some cases much less than 60 minutes, forexample as little as about 15 to about 45 minutes, after oraladministration, if it is formulated and administered in such a way as togive a particular pharmacokinetic profile as defined below.

[0012] Accordingly, there is now provided a therapeutic methodcomprising orally administering to a mammalian, preferably human,subject in need of analgesia an effective pain-relieving amount of acomposition comprising celecoxib (herein also referred to as a celecoxibcomposition) formulated in such a way as to provide, when tested infasting humans in accordance with standard pharmacokinetic practice, ablood plasma concentration profile of celecoxib in which a concentrationof about 250 ng/ml is attained not later than about 30 minutes afteroral administration. The plasma concentrations of 250 ng/ml or greaterachieved by the compositions and methods of the present invention at orbefore 30 minutes after oral administration and, more preferably, at orbefore 15 minutes after oral administration, are effectivepain-relieving plasma concentrations.

[0013] It has not previously been known that fast absorption ofcelecoxib, as indicated by such a blood plasma concentration profile, isimportant in achieving fast onset of analgesic response. As noted above,celecoxib is known to be extensively bound to plasma albumin followingoral administration (Davies et al., supra) such that one could not havepredicted that a particular plasma concentration would produceanalgesia.

[0014] There is also provided a method of use of celecoxib, formulatedin such a way as to provide, when tested in an effective pain-relievingamount in fasting humans in accordance with standard pharmacokineticpractice, a blood plasma concentration profile of celecoxib in which aconcentration of about 250 ng/ml is attained not later than about 30minutes after oral administration, in preparation of a medicament forrapid relief of pain in a mammalian, preferably human, subject.

[0015] The phrase “in need of analgesia” as applied to a subject hereinembraces a subject suffering mild to intense pain at the time ofadministration of the celecoxib composition, as well as a subject thatcan reasonably be expected to have an imminent onset of mild to intensepain, e.g., within about 1 to about 2 hours and especially within about30 minutes, if no analgesic is administered. An illustrative example ofa situation where a subject can reasonably be expected to have such animminent onset of pain is a period immediately following surgery underlocal anesthetic, as effects of the local anesthetic wear off.

[0016] What constitutes an effective pain-relieving amount, or dose, ofa celecoxib composition according to the invention depends, among otherfactors, on the body weight of the subject and the intensity of the painbeing treated. Normally an effective celecoxib dose will be found in therange of about 1 to about 6 mg/kg body weight. For an average 75 kgsubject, this range equates to a celecoxib dose of about 75 to about 450mg. Proportionately smaller or larger doses can be appropriate forsubjects having lesser or greater body weight. Such a dose can beadministered as needed, but typically administration 1 to about 4 timesper day, in most cases 1 or 2 times a day, provides adequate continuingrelief of pain.

[0017] An “effective pain-relieving concentration” or “effectivepain-relieving plasma concentration” as used herein is intended to meana plasma level in a patient which when tested in a standardized testinvolving patient scoring of the severity of pain, achieves a mean scoreindicating pain relief. In one such test as described hereinbelow,patients score pain on a scale of from 0 (no reduction in severity ofpain) to 4 (complete relief of pain) and a mean score equal to orgreater than a given value is deemed to constitute effectivepain-relief. A mean score of 0.5 or greater and, more preferably, 1.0 orgreater in such a test, as exemplified herein, is deemed to constituteeffective pain relief. The skilled artisan will appreciate, however,that other approaches can be used to assess the severity of pain andrelief from such pain.

[0018] Thus, one aspect of the present invention involves a therapeuticmethod for analgesia in which a composition comprising celecoxib isadministered orally to a subject, in a formulation which providesdetectable pain relief not later than about 30 minutes after oraladministration. By “detectable pain relief”, it is meant that theformulation produces effective pain relief which is measurable by astandard method such as described above. For example, a formulation,which achieves a mean score of 0.5 or greater and, more preferably, 1.0or greater on a scale of from 0 to 4 in a testing system as describedabove, is deemed to provide detectable pain relief. The invention is notlimited to use of any particular type of formulation, so long as itexhibits the pharmacokinetic profile defined herein. Examples ofsuitable formulation types are described below.

[0019] Protocols for conducting human pharmacokinetic studies are wellknown in the art and any standard protocol can be used to determinewhether a particular celecoxib formulation satisfies the pharmacokineticcriteria set out herein. An example of a suitable protocol is describedbelow.

[0020] An advantage of the present invention is that relief of pain,even intense pain as can occur, for example, following oral, general ororthopedic surgery, is achieved significantly faster, i.e., in asignificantly shorter time after administration, than is achievable withstandard formulations of celecoxib.

[0021] A further advantage is that, by contrast with pain relief methodsinvolving NSAIDs lacking selectivity for inhibition of COX-2, rapidrelief of pain can be obtained without the side-effects commonlyassociated with COX-1 inhibition. Thus the method of the presentinvention is especially suitable where NSAIDs are contraindicated, forexample in patients with peptic ulcers, gastritis, regional enteritis,ulcerative colitis or diverticulitis, patients with a recurrent historyof gastrointestinal lesions, patients with gastrointestinal bleeding,coagulation disorders including anemia such as hypothrombinemia,hemophilia and other bleeding problems, or kidney disease, patientsprior to surgery, or patients taking anticoagulants.

[0022] Other features and advantages of the invention will be in partapparent and in part pointed out hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023]FIG. 1 shows blood plasma concentration profiles of celecoxibadministered as a single oral dose of 200 mg, in the form of a capsule(Celebrex® 200 mg, Pharmacia Corporation) or in the form of a finesuspension in apple juice as described in Example 1.

[0024]FIG. 2 shows relief of post-surgical pain experienced over a12-hour period following administration of a single oral dose of (1) 200mg celecoxib in the form of a capsule (Celebrex® 200 mg, PharmaciaCorporation), (2) 400 mg ibuprofen in the form of a capsule, (3) 200 mgcelecoxib in the form of a fine suspension in apple juice as describedin Example 1, or (4) placebo.

[0025]FIG. 3 shows more clearly than FIG. 2 the relief of post-surgicalpain experienced in the first 2 hours following administration of theabove treatments (1) through (4), to emphasize differences amongtreatments in time of onset of pain relief.

[0026]FIG. 4 shows blood plasma concentration profiles of celecoxibadministered as a single oral dose of 200 mg, in the form of a capsule(Celebrex® 200 mg, Pharmacia Corporation), in the form of a suspensionin apple juice as described in Example 2, or in the form of TestComposition 1 of Example 2.

DETAILED DESCRIPTION OF THE INVENTION

[0027] The present invention provides a method of rapidly relieving painin a mammalian subject, the method comprising orally administering tothe subject an effective pain-relieving amount of a compositioncomprising celecoxib formulated in such a way as to provide, when testedin fasting humans in accordance with standard pharmacokinetic practice,a blood plasma concentration profile of celecoxib in which aconcentration of about 250 ng/ml is attained not later than about 30minutes after oral administration. The plasma concentration of 250 ng/mlachieved by the formulations of the present invention, constitutes an“an effective pain-relieving plasma concentration.”

[0028] The method of the invention can be used to relieve acute orchronic pain, but is particularly well-suited to acute pain indicationssuch as post-surgical pain or post-traumatic pain. The method of theinvention is useful for treatment of non-human mammalian subjects orpatients, including domestic, farm and exotic animals, such as forexample dogs horses, zoo animals and the like, but is primarily usefulfor treatment of human subjects or patients.

[0029] Celecoxib used in the method of the invention can be prepared bya process known per se, for example by processes described in U.S. Pat.No. 5,466,863 to Talley et al. or in U.S. Pat. No. 5,892,053 to Zhi &Newaz.

[0030] A suitable dose of celecoxib, administered according to themethod of the invention, is typically in the range of about 1 to about 6mg/kg body weight, preferably about 1.3 to about 5.3 mg/kg body weightand more preferably about 2 to about 3.5 mg/kg body weight, for exampleabout 2.7 mg/kg body weight. Depending on the body weight of thesubject, a suitable dosage amount of celecoxib is typically about 50 toabout 400 mg, preferably about 100 to about 300 mg. Surprisingly goodresults can be obtained with dosage amounts less than 300 mg, such asabout 100 to about 275 mg, or about 150 to about 250 mg, for exampleabout 200 mg.

[0031] The doses set out above relate to a single administration, andcan be repeated as needed. Generally no more than about 4 doses per daywill be needed, and in most cases 1 or 2 doses per day will be foundsufficient.

[0032] A key to the present invention is selecting a formulation thatprovides a pharmacokinetic profile wherein a threshold blood plasmaconcentration of celecoxib of at least about 250 ng/ml is attained notlater than about 30 minutes after oral administration. Thisanalgesically effective blood concentration is achieved in the presentinvention by utilizing a composition containing celecoxib in a rapidlybioavailable formulation, i.e. a “fast-acting formulation”. Thecelecoxib is present in the composition at dose levels as discussedabove, which are typically used in formulations which do not achievesuch plasma concentrations shortly after administration, i.e. withinabout 30 minutes and, more preferably, within about 15 minutes afteroral administration.

[0033] In preferred methods, a formulation is selected providing ahigher concentration than about 250 ng/ml within about 30 minutes. Forexample, a formulation can be expected to be particularly effective forrelief of pain if a blood plasma concentration of at least about 300ng/ml, more preferably at least about 400 ng/ml and most preferably atleast about 500 ng/ml, is attained within about 30 minutes followingoral administration of the formulation. There is no critical upper limitof blood plasma concentration so long as the dosage amounts set outabove are not significantly exceeded; however it is likely that nosignificant incremental benefit will be obtained from blood plasmaconcentrations of celecoxib greatly in excess of about 500 ng/ml, forexample in excess of about 1000 ng/ml, within the first 30 minutes.

[0034] Preferably, a threshold blood plasma concentration of celecoxibof about 250 ng/ml is attained not later than about 15 minutes afteroral administration of the formulation.

[0035] In a particularly preferred embodiment the formulation provides ablood plasma concentration of celecoxib that attains about 300 ng/ml notlater than about 30 minutes, most preferably not later than about 15minutes, after oral administration.

[0036] In another particularly preferred embodiment the formulationexhibits a T_(max) not greater than about 1.25 hours, most preferablynot greater than about 1 hour.

[0037] In yet another particularly preferred embodiment the formulationexhibits, in comparative pharmacokinetic testing versus a standardcommercial formulation of celecoxib, such as Celebrex® 200 mg capsulesof Pharnacia Corporation, a T_(max) not greater than about 50%, evenmore preferably not greater than about 33%, and most preferably notgreater than about 25%, of the T_(max), exhibited by said standardcommercial formulation.

[0038] Any standard pharmacokinetic protocol can be used to determineblood plasma concentration profile in humans following oraladministration of a celecoxib formulation, and thereby establish whetherthat formulation meets the pharmacokinetic criteria set out herein.

[0039] Illustratively, a randomized single-dose crossover study can beperformed using a group of healthy adult human subjects. The number ofsubjects is sufficient to provide adequate control of variation in astatistical analysis, and is typically about 10 or greater, although forcertain purposes a smaller group can suffice. Each subject receives, byoral administration at time zero, a single dose (e.g., 200 mg) of a testformulation of celecoxib, normally at around 8 am following an overnightfast. The subject continues to fast and remains in an upright positionfor about 4 hours after administration of the celecoxib formulation.Blood samples are collected from each subject before administration(e.g., 15 minutes prior to administration) and at several intervalsafter administration. For the present purpose it is preferred to takeseveral samples within the first hour, and to sample less frequentlythereafter. Illustratively, blood samples can be collected 15, 30, 45,60 and 90 minutes after administration, then every hour from 2 to 10hours after administration. Optionally additional blood samples can betaken later, for example 12 and 24 hours after administration. If thesame subjects are to be used for study of a second test formulation, aperiod of at least 7 days is allowed to elapse before administration ofthe second formulation. Plasma is separated from the blood samples bycentrifugation and the separated plasma is analyzed for celecoxib by avalidated high performance liquid chromatography (HPLC) procedure with alower limit of detection of 10 ng/ml (see for example, Paulson et al.,Drug Metab. Dispos. 27:1133-1142, 1999; Paulson et al., Drug Metab.Dispos. 28:308-314, 2000; Davies et al, supra). Plasma concentrationsof-celecoxib referenced herein are intended to mean total celecoxibconcentrations including both free and bound celecoxib as determinedupon extraction from the plasma sample and HPLC detection according tomethods known in the art such as those identified above.

[0040] Any formulation giving the desired pharmacokinetic profile issuitable for administration according to the present method. Oneexemplary type of formulation giving such a profile has celecoxibultra-finely dispersed in a liquid medium. If the liquid medium is onein which celecoxib is of very low solubility, for example an aqueousmedium such as water or fruit juice, the celecoxib is present assuspended particles. The smaller the particles, the higher is theprobability that the formulation will exhibit the presently desiredpharmacokinetic profile. The ultimate in particle size reduction isrepresented by a true solution of celecoxib in a pharmaceuticallyacceptable solvent such as polyethylene glycol (PEG), e.g., PEG havingan average molecular weight of about 400 (PEG-400), or a glycol ether,e.g., diethylene glycol monoethyl ether (DGME).

[0041] In a formulation having celecoxib in solid particulate form, itwill generally be found necessary for practice of the present inventionto provide celecoxib in a particle size range wherein D₉₀ is less thanabout 10 μm, for example about 10 nm to about 10 μm. (D₉₀ is a diametersuch that 90% by weight of the particles are smaller than this diameterin their longest dimension.) Preferably, D₉₀ is less than about 2 μm.

[0042] Optionally, the celecoxib is nanoparticulate, i.e., having D₉₀less than about 1 μm. In nanoparticulate celecoxib formulations, weightaverage particle size is typically about 100 nm to about 800 nm, forexample about 150 nm to about 600 nm, or about 200 nm to about 400 nm.Pharmaceutical compositions comprising such nanoparticulate celecoxibformulations are useful in methods of the present invention.

[0043] In a related embodiment, pharmaceutical compositions usefulherein comprise celecoxib formulations wherein the celecoxib has a D₂₅particle size of about 450 nm to about 1000 nm, and more preferablyabout 500 nm to about 900 nm, the formulation providing at least asubstantially similar C_(max) and/or at most a substantially similarT_(max) by comparison with an otherwise similar formulation having a D₂₅particle size of less than 400 nm, and/or providing a substantiallygreater C_(max) and/or a substantially shorter T_(max) by comparisonwith an otherwise similar formulation having a D₂₅ particle size largerthan 1000 nm. (D₂₅ is a diameter such that 25% by weight of theparticles are smaller than this diameter in their longest dimension.)

[0044] In another related embodiment, pharmaceutical compositions usefulherein comprise celecoxib formulations wherein the celecoxib is presentin solid particles, about 25% to 100% by weight of which have a particlesize of about 450 nm to about 1000 nm, preferably about 500 nm to about900 nm.

[0045] In yet another related embodiment, pharmaceutical compositionsuseful herein comprise nanoparticulate celecoxib formulations whereinthe celecoxib is present in solid particles having a weight averageparticle size of about 450 nm to about 1000 nm, preferably about 500 nmto about 900 nm, the composition providing at least a substantiallysimilar C_(max) and/or at most a substantially similar T_(max) bycomparison with an otherwise similar composition having a weight averageparticle size of less than 400 nm, and/or providing a substantiallygreater C_(max) and/or a substantially shorter T_(max) by comparisonwith an otherwise similar composition having a weight average particlesize larger than 1000 nm. For purposes of this description, “weightaverage particle size” can be considered synonymous with D₅₀ particlesize.

[0046] Numerous processes for preparation of nanoparticulatecompositions of therapeutic agents are known. Some of these processesuse mechanical means, such as milling, to reduce particle size to a nanorange, and others precipitate nano-sized particles from solution.Illustrative processes are disclosed in the patent publications citedbelow.

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[0080] International Patent Publication No. WO 93/25190.

[0081] International Patent Publication No. WO 96/24336.

[0082] International Patent Publication No. WO 97/14407.

[0083] International Patent Publication No. WO 98/35666.

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[0085] International Patent Publication No. WO 00/18374.

[0086] International Patent Publication No. WO 00/27369.

[0087] International Patent Publication No. WO 00/30615.

[0088] One of ordinary skill in the art will readily adapt the processestherein described to preparation of celecoxib in nanoparticulate form.

[0089] One method of providing suspended particulate celecoxib in aparticle size range suitable for practice of the present inventioninvolves a first step of dissolving the celecoxib in a suitable solventsuch as ethanol. Preferably the amount of solvent used is kept to aminimum, but must be sufficient to fully dissolve the celecoxib.Preferably a suitable amount of a wetting agent such as polysorbate 80is also added to the solvent; this can be done before or after,preferably before, addition of the celecoxib. Celecoxib can be added tothe ethanol as technical drug, i.e., without the presence of excipients,or in the form of a celecoxib formulation comprising one or moreexcipients such as diluents, e.g., lactose and/or microcrystallinecellulose, disintegrants, e.g., croscarmellose sodium, binding agents,e.g., polyvinylpyrrolidone, wetting agents, e.g., sodium lauryl sulfate,and lubricants, e.g., magnesium stearate.

[0090] In a second step, the resulting solution of celecoxib is added toan aqueous liquid and vigorously agitated, for example by stirring. Thevolume of the aqueous liquid is much greater than the volume of thecelecoxib solution. The effect of the second step is to precipitatecelecoxib as a fine suspension in the aqueous liquid. The aqueous liquidcan be water and can include other ingredients, such as one or morematerials selected from sweetening agents, flavoring agents and coloringagents. The aqueous liquid can be a beverage such as a fruit juice,e.g., apple juice, grape juice, cranberry juice, orange juice, etc.

[0091] If the resulting suspension is allowed to stand, the celecoxibparticles tend to agglomerate and/or increase in size by crystal growth.These processes can occur relatively quickly. It is therefore importantthat the suspension be administered as soon as possible afterpreparation, preferably not more than about 15 minutes and mostpreferably not more than about 5 minutes after preparation. It may alsobe desirable to add substances which delay, diminish or interfere withthe formation of celecoxib crystals.

[0092] Finely divided particulate or nanoparticulate celecoxib is notnecessarily administered in suspension. It can be administered as asolid dosage form such as a capsule or tablet, provided disintegrationof the solid dosage form to release celecoxib into the gastrointestinalfluid occurs rapidly enough to generate the presently desiredpharmacokinetic profile. Similarly, a solution of celecoxib can beadministered in a capsule, such as a hard or soft capsule having a wallcomprising gelatin or hydroxypropylmethylcellulose (HPMC), provided thecapsule wall dissolves or disintegrates rapidly enough ingastrointestinal fluid to enable the celecoxib thus released to beabsorbed into the bloodstream and generate the presently desiredpharmacokinetic profile.

[0093] Celecoxib is highly hydrophobic; inclusion in the formulation ofa wetting agent can provide wetting of celecoxib particles and canimprove absorption. This can also help provide a pharmacokinetic profileconsistent with the present invention, even where particle size is notideal. Any suitable wetting agent can be used. Surfactants, hydrophilicpolymers and certain clays can be useful as wetting agents. Non-limitingexamples of suitable surfactants include benzalkonium chloride,benzethonium chloride, cetylpyridinium chloride, dioctyl sodiumsulfosuccinate, nonoxynol 9, nonoxynol 10, octoxynol 9, poloxamers,polyoxyethylene (8) caprylic/capric mono- and diglycerides (e.g.,Labrasol™ of Gattefossé), polyoxyethylene (35) castor oil,polyoxyethylene (20) cetostearyl ether, polyoxyethylene (40)hydrogenated castor oil, polyoxyethylene (10) oleyl ether,polyoxyethylene (40) stearate, polysorbate 20, polysorbate 40,polysorbate 60, polysorbate 80 (e.g., Tween™ 80 of ICI), propyleneglycol laurate (e.g., LauroglyCol™ of Gattefosse), sodium laurylsulfate, sorbitan monolaurate, sorbitan monooleate, sorbitanmonopalmitate, sorbitan monostearate, tyloxapol, and mixtures thereof.Presently preferred examples include polysorbate 80 and sodium laurylsulfate.

[0094] Formulations useful in the present invention can be imbibableliquids or unit dosage forms. Unit dosage forms useful in the inventiontypically contain about 10 mg to about 400 mg of celecoxib, for example,a 10, 20, 37.5, 50, 75, 100, 125, 150, 175, 200, 250, 300, 350 or 400 mgdose of celecoxib. Preferred unit dosage forms contain about 50 mg toabout 400 mg of celecoxib. More preferred unit dosage forms containabout 100 mg to about 200 mg of celecoxib.

[0095] In an imbibable formulation, celecoxib can be present at anysuitable concentration. Preferably the concentration is sufficientlyhigh that the volume of liquid that has to be imbibed is notinconveniently great for the patient. For example, for a 200 mg dose, itis preferable that the concentration of celecoxib in an imbibablesolution or suspension be not less than about 0.1% weight/volume, sothat the volume of solution or suspension to be imbibed is not greaterthan about 200 ml.

[0096] In a unit dosage form, celecoxib is present at a minimumconcentration of about 1%, preferably about 4%, more preferably about10%, and still more preferably about 20%, by weight. The maximumconcentration of celecoxib in a unit dosage form depends, among otherfactors, on the excipients present in the formulation, but is normallyabout 90%, preferably about 75% and more preferably about 50%, byweight.

[0097] In a particular embodiment of the invention, a first celecoxibformulation providing the pharmacokinetic profile required herein isco-administered with a second celecoxib formulation that generates adifferent pharmacokinetic profile, specifically one exhibiting slowerabsorption into the bloodstream and therefore a longer T_(max), andtypically a lower C_(max). The combination of fast pain relief providedby the first formulation and longer-lasting pain relief provided by thesecond formulation can reduce the dose frequency required.Alternatively, the second formulation can contain a selective COX-2inhibitory drug other than celecoxib.

[0098] Preferably where co-administration of a “fast-acting” formulationand a “longer-lasting” formulation is desired, the two formulations arecombined within a single composition, for example a dual-releasecomposition.

[0099] While methods of the present invention are primarily directedtowards treatment of fast onset indications such as pain relief,celecoxib compositions useful in such methods are also contemplated tobe useful in treatment and/or prevention of a wide range of conditionsand disorders mediated by COX-2, including but not restricted todisorders characterized by inflammation, pain and/or fever. Suchcompositions are especially useful as anti-inflammatory agents, such asin treatment of arthritis, with the additional benefit of havingsignificantly less harmful side effects than compositions ofconventional nonsteroidal anti-inflammatory drugs (NSAIDs) that lackselectivity for COX-2 over COX-1. In particular, such compositions havereduced potential for gastrointestinal toxicity and gastrointestinalirritation including upper gastrointestinal ulceration and bleeding,reduced potential for renal side effects such as reduction in renalfunction leading to fluid retention and exacerbation of hypertension,reduced effect on bleeding times including inhibition of plateletfunction, and possibly a lessened ability to induce asthma attacks inaspirin-sensitive asthmatic subjects, by comparison with compositions ofconventional NSAIDs. Thus compositions useful in methods of theinvention are particularly useful as an alternative to conventionalNSAIDs where such NSAIDs are contraindicated, for example in patientswith peptic ulcers, gastritis, regional enteritis, ulcerative colitis,diverticulitis or with a recurrent history of gastrointestinal lesions;gastrointestinal bleeding, coagulation disorders including anemia suchas hypoprothrombinemia, hemophilia or other bleeding problems; kidneydisease; or in patients prior to surgery or patients takinganticoagulants.

[0100] Such compositions are useful to treat a variety of arthriticdisorders, including but not limited to rheumatoid arthritis,spondyloarthropathies, gouty arthritis; osteoarthritis, systemic lupuserythematosus and juvenile arthritis.

[0101] Such compositions are also useful in treatment of asthma,bronchitis, menstrual cramps, preterm labor, tendinitis, bursitis,allergic neuritis, cytomegalovirus infectivity, apoptosis includingHIV-induced apoptosis, lumbago, liver disease including hepatitis,skin-related conditions such as psoriasis, eczema, acne, bums,dermatitis and ultraviolet radiation damage including sunburn, andpost-operative inflammation including that following ophthalmic surgerysuch as cataract surgery or refractive surgery.

[0102] Such compositions are useful to treat gastrointestinal conditionssuch as inflammatory bowel disease, Crohn's disease, gastritis,irritable bowel syndrome and ulcerative colitis.

[0103] Such compositions are useful in treating inflammation in suchdiseases as migraine headaches, periarteritis nodosa, thyroiditis,aplastic anemia, Hodgkin's disease, sclerodoma, rheumatic fever, type Idiabetes, neuromuscular junction disease including myasthenia gravis,white matter disease including multiple sclerosis, sarcoidosis,nephrotic syndrome, Behcet's syndrome, polymyositis, gingivitis,nephritis, hypersensitivity, swelling occurring after injury includingbrain edema, myocardial ischemia, and the like.

[0104] Such compositions are useful in treatment of ophthalmic diseases,such as retinitis, conjunctivitis, retinopathies, uveitis, ocularphotophobia, and of acute injury to the eye tissue.

[0105] Such compositions are useful in treatment of pulmonaryinflammation, such as that associated with viral infections and cysticfibrosis, and in bone resorption such as that associated withosteoporosis.

[0106] Such compositions are useful for treatment of certain centralnervous system disorders, such as cortical dementias includingAlzheimer's disease, neurodegeneration, and central nervous systemdamage resulting from stroke, ischemia and trauma. The term “treatment”in the present context includes partial or total inhibition ofdementias, including Alzheimer's disease, vascular dementia,multi-infarct dementia, pre-senile dementia, alcoholic dementia andsenile dementia.

[0107] Such compositions are useful in treatment of allergic rhinitis,respiratory distress syndrome, endotoxin shock syndrome and liverdisease.

[0108] Such compositions are useful in treatment of pain, including butnot limited to postoperative pain, dental pain, muscular pain, and painresulting from cancer. For example, such compositions are useful forrelief of pain, fever and inflammation in a variety of conditionsincluding rheumatic fever, influenza and other viral infectionsincluding common cold, low back and neck pain, dysmenorrhea, headache,toothache, sprains and strains, myositis, neuralgia, synovitis,arthritis, including rheumatoid arthritis, degenerative joint diseases(osteoarthritis), gout and ankylosing spondylitis, bursitis, burns, andtrauma following surgical and dental procedures.

[0109] Such compositions are useful for treating and preventinginflammation-related cardiovascular disorders, including vasculardiseases, coronary artery disease, aneurysm, vascular rejection,arteriosclerosis, atherosclerosis including cardiac transplantatherosclerosis, myocardial infarction, embolism, stroke, thrombosisincluding venous thrombosis, angina including unstable angina, coronaryplaque inflammation, bacterial-induced inflammation includingChlamydia-induced inflammation, viral induced inflammation, andinflammation associated with surgical procedures such as vasculargrafting including coronary artery bypass surgery, revascularizationprocedures including angioplasty, stent placement, endarterectomy, orother invasive procedures involving arteries, veins and capillaries.

[0110] Such compositions are useful in treatment of angiogenesis-relateddisorders in a subject, for example to inhibit tumor angiogenesis. Suchcompositions are useful in treatment of neoplasia, including metastasis;ophthalmological conditions such as comeal graft rejection, ocularneovascularization, retinal neovascularization includingneovascularization following injury or infection, diabetic retinopathy,macular degeneration, retrolental fibroplasia and neovascular glaucoma;ulcerative diseases such as gastric ulcer; pathological, butnon-malignant, conditions such as hemangiomas, including infantilehemaginomas, angiofibroma of the nasopharynx and avascular necrosis ofbone; and disorders of the female reproductive system such asendometriosis.

[0111] Such compositions are useful in prevention and treatment ofbenign and malignant tumors and neoplasia including cancer, such ascolorectal cancer, brain cancer, bone cancer, epithelial cell-derivedneoplasia (epithelial carcinoma) such as basal cell carcinoma,adenocarcinoma, gastrointestinal cancer such as lip cancer, mouthcancer, esophageal cancer, small bowel cancer, stomach cancer, coloncancer, liver cancer, bladder cancer, pancreas cancer, ovary cancer,cervical cancer, lung cancer, breast cancer, skin cancer such assquamous cell and basal cell cancers, prostate cancer, renal cellcarcinoma, and other known cancers that effect epithelial cellsthroughout the body. Neoplasias for which compositions of the inventionare contemplated to be particularly useful are gastrointestinal cancer,Barrett's esophagus, liver cancer, bladder cancer, pancreatic cancer,ovarian cancer, prostate cancer, cervical cancer, lung cancer, breastcancer and skin cancer. Such compositions can also be used to treatfibrosis that occurs with radiation therapy. Such compositions can beused to treat subjects having adenomatous polyps, including those withfamilial adenomatous polyposis (FAP). Additionally, such compositionscan be used to prevent polyps from forming in patients at risk of FAP.

[0112] Such compositions inhibit prostanoid-induced smooth musclecontraction by inhibiting synthesis of contractile prostanoids and hencecan be of use in treatment of dysmenorrhea, premature labor, asthma andeosinophil-related disorders. They also can be of use for decreasingbone loss particularly in postmenopausal women (i.e., treatment ofosteoporosis), and for treatment of glaucoma.

[0113] Because of the rapid onset of therapeutic effect that can beexhibited by compositions useful in methods of the invention, thesecompositions have particular advantages over prior formulations fortreatment of acute COX-2 mediated disorders, especially for relief ofpain, for example in headache, including sinus headache and migraine.

[0114] Celecoxib compositions useful in methods of the present inventioncan be used in combination therapies with opioids and other analgesics,including narcotic analgesics, Mu receptor antagonists, Kappa receptorantagonists, non-narcotic (i.e., non-addictive) analgesics, monoamineuptake inhibitors, adenosine regulating agents, cannabinoid derivatives,Substance P antagonists, neurokinin-1 receptor antagonists and sodiumchannel blockers, among others. Preferred combination therapies comprisea composition useful in methods of the invention with one or morecompounds selected from aceclofenac, acemetacin, e-acetamidocaproicacid, acetaminophen, acetaminosalol, acetanilide, acetylsalicylic acid(aspirin), S-adenosylmethionine, alclofenac, alfentanil, allylprodine,alminoprofen, aloxiprin, alphaprodine, aluminum bis(acetylsalicylate),amfenac, aminochlorthenoxazin, 3-amino-4-hydroxybutyric acid,2-amino-4-picoline, aminopropylon, aminopyrine, amixetrine, ammoniumsalicylate, ampiroxicam, amtolmetin guacil, anileridine, antipyrine,antipyrine salicylate, antrafenine, apazone, bendazac, benorylate,benoxaprofen, benzpiperylon, benzydamine, benzylmorphine, bermoprofen,bezitramide, a-bisabolol, bromfenac, p-bromoacetanilide,5-bromosalicylic acid acetate, bromosaligenin, bucetin, bucloxic acid,bucolome, bufexamac, bumadizon, buprenorphine, butacetin, butibufen,butophanol, calcium acetylsalicylate, carbamazepine, carbiphene,carprofen, carsalam, chlorobutanol, chlorthenoxazin, choline salicylate,cinchophen, cinmetacin, ciramadol, clidanac, clometacin, clonitazene,clonixin, clopirac, clove, codeine, codeine methyl bromide, codeinephosphate, codeine sulfate, cropropamide, crotethamide, desomorphine,dexoxadrol, dextromoramide, dezocine, diampromide, diclofenac sodium,difenamizole, difenpiramide, diflunisal, dihydrocodeine,dihydrocodeinone enol acetate, dihydromorphine, dihydroxyaluminumacetylsalicylate, dimenoxadol, dimepheptanol, dimethylthiambutene,dioxaphetyl butyrate, dipipanone, diprocetyl, dipyrone, ditazol,droxicam, emorfazone, enfenamic acid, epirizole, eptazocine, etersalate,ethenzamide, ethoheptazine, ethoxazene, ethylmethylthiambutene,ethylmorphine, etodolac, etofenamate, etonitazene, eugenol, felbinac,fenbufen, fenclozic acid, fendosal, fenoprofen, fentanyl, fentiazac,fepradinol, feprazone, floctafenine, flufenamic acid, flunoxaprofen,fluoresone, flupirtine, fluproquazone, flurbiprofen, fosfosal, gentisicacid, glafenine, glucametacin, glycol salicylate, guaiazulene,hydrocodone, hydromorphone, hydroxypethidine, ibufenac, ibuprofen,ibuproxam, imidazole salicylate, indomethacin, indoprofen, isofezolac,isoladol, isomethadone, isonixin, isoxepac, isoxicam, ketobemidone,ketoprofen, ketorolac, p-lactophenetide, lefetamine, levorphanol,lofentanil, lonazolac, lornoxicam, loxoprofen, lysine acetylsalicylate,magnesium acetylsalicylate, meclofenamic acid, mefenamic acid,meperidine, meptazinol, mesalamine, metazocine, methadone hydrochloride,methotrimeprazine, metiazinic acid, metofoline, metopon, mofebutazone,mofezolac, morazone, morphine, morphine hydrochloride, morphine sulfate,morpholine salicylate, myrophine, nabumetone, nalbuphine, 1-naphthylsalicylate, naproxen, narceine, nefopam, nicomorphine, nifenazone,niflumic acid, nimesulide, 5′-nitro-2′-propoxyacetanilide,norlevorphanol, normethadone, normorphine, norpipanone, olsalazine,opium, oxaceprol, oxametacine, oxaprozin, oxycodone, oxymorphone,oxyphenbutazone, papaveretum, paranyline, parsalmide, pentazocine,perisoxal, phenacetin, phenadoxone, phenazocine, phenazopyridinehydrochloride, phenocoll, phenoperidine, phenopyrazone, phenylacetylsalicylate, phenylbutazone, phenyl salicylate, phenyramidol,piketoprofen, piminodine, pipebuzone, piperylone, piprofen, pirazolac,piritramide, piroxicam, pranoprofen, proglumetacin, proheptazine,promedol, propacetamol, propiram, propoxyphene, propyphenazone,proquazone, protizinic acid, ramifenazone, remifentanil, rimazoliummetilsulfate, salacetamide, salicin, salicylamide, salicylamide o-aceticacid, salicylsulfuric acid, salsalte, salverine, simetride, sodiumsalicylate, sufentanil, sulfasalazine, sulindac, superoxide dismutase,suprofen, suxibuzone, talniflumate, tenidap, tenoxicam, terofenamate,tetrandrine, thiazolinobutazone, tiaprofenic acid, tiaramide, tilidine,tinoridine, tolfenamic acid, tolmetin, tramadol, tropesin, viminol,xenbucin, ximoprofen, zaltoprofen and zomepirac (see The Merck Index,12th Edition (1996), Therapeutic Category and Biological Activity Index,lists therein headed “Analgesic”, “Anti-inflammatory” and“Antipyretic”).

[0115] Particularly preferred combination therapies comprise use of sucha celecoxib composition with an opioid compound, more particularly wherethe opioid compound is codeine, meperidine, morphine or a derivativethereof.

[0116] The compound to be administered in combination with a celecoxibcomposition useful in methods of the invention can be formulatedseparately from said composition or co-formulated with said composition.Where a celecoxib composition is co-formulated with a second drug, forexample an opioid drug, the second drug can be formulated inimmediate-release, rapid-onset, sustained-release or dual-release form.

[0117] In an embodiment of the invention, particularly where the COX-2mediated condition is headache or migraine, the celecoxib composition isadministered in combination therapy with a vasomodulator, preferably axanthine derivative having vasomodulatory effect, more preferably analkylxanthine compound.

[0118] Combination therapies wherein an alkylxanthine compound isco-administered with a celecoxib composition as provided herein areembraced by the present embodiment of the invention whether or not thealkylxanthine is a vasomodulator and whether or not the therapeuticeffectiveness of the combination is to any degree attributable to avasomodulatory effect. The term “alkylxanthine” herein embraces xanthinederivatives having one or more C₁₋₄ alkyl, preferably methyl,substituents, and pharmaceutically acceptable salts of such xanthinederivatives. Dimethylxanthines and trimethylxanthines, includingcaffeine, theobromine and theophylline, are especially preferred. Mostpreferably, the alkylxanthine compound is caffeine.

[0119] The total and relative dosage amounts of the celecoxibcomposition and of the vasomodulator or alkylxanthine are selected to betherapeutically and/or prophylactically effective for relief of painassociated with the headache or migraine. Suitable dosage amounts willdepend on the particular patient and the particular vasomodulator oralkylxanthine selected. For example, in a combination therapy withcelecoxib and caffeine, typically the celecoxib will be administered ina daily dosage amount of about 50 mg to about 1000 mg, preferably about100 mg to about 600 mg, and the caffeine in a daily dosage amount ofabout 1 mg to about 500 mg, preferably about 10 mg to about 400 mg, morepreferably about 20 mg to about 300 mg.

[0120] The vasomodulator or alkylxanthine component of the combinationtherapy can be administered in any suitable dosage form by any suitableroute, preferably orally. The vasomodulator or alkylxanthine canoptionally be coformulated with the celecoxib composition in a singleoral dosage form. Thus a solution or solution/suspension formulationuseful in methods of the invention optionally comprises both celecoxiband a vasomodulator or alkylxanthine such as caffeine, in total andrelative amounts consistent with the dosage amounts set out hereinabove.

[0121] The phrase “in total and relative amounts effective to relievepain”, with respect to amounts of celecoxib and a vasomodulator oralkylxanthine in a composition of the present embodiment, means thatthese amounts are such that (a) together these components are effectiveto relieve pain, and (b) each component is or would be capable ofcontribution to a pain-relieving effect if the other component is orwere not present in so great an amount as to obviate such contribution.

EXAMPLES

[0122] The following Examples are provided for illustrative purposesonly and are not to be interpreted as limiting the scope of the presentinvention. The Examples will permit better understanding of theinvention and better perception of its advantages.

Example 1

[0123] A single-center, single-dose, double-blind, placebo controlled,parallel group 24 hour study was conducted in a total of 200 patientsexperiencing moderate to severe post-dental surgery pain. Patients werein an immediate post-surgical phase following extraction of 2 or moreimpacted third molars requiring bone removal. Patients were stratifiedbased on baseline pain intensity and allocated randomly to fourtreatment groups for oral dosing:

[0124] 1. Celecoxib 200 mg capsule (Celebrex® 200 mg).

[0125] 2. Ibuprofen 400 mg capsule.

[0126] 3. Celecoxib 200 mg fine suspension.

[0127] 4. Placebo.

[0128] The celecoxib fine suspension was prepared by dissolvingcelecoxib in ethanol containing 5% polysorbate 80 and adding theresulting mixture to apple juice. The fine suspension was administeredwithin 5 minutes of preparation.

[0129] Assessment of pain relief for each patient, based on interviewwith the patient, was made on a 0-4 scale at the time of dosing andagain 15, 30, 45 and 60 minutes and 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,12 and 24 hours after dosing, or until rescue medication was required. Ascore of 0 was assigned where the patient reported no reduction inseverity of pain, a score of 4 was assigned where the patient reportedcomplete relief of pain, and scores of 1, 2 and 3 were assigned tointermediate degrees of pain relief.

[0130] Each patient also recorded the time to onset of analgesia bypressing a first stop-watch at the time a perceptible reduction inseverity of pain was first noticed, and a second stop-watch at the timea reduction in severity of pain was considered meaningful by thepatient.

[0131] Blood samples for pharmacokinetic analysis were taken immediatelybefore dosing and again 15, 30, 45 and 60 minutes and 1.5, 2, 3, 4, 5,6, 7, 8, 9, 10, 11, 12 and 24 hours after dosing. Plasma was separatedfrom the blood samples by centrifugation and the separated plasma wasanalyzed for celecoxib by a validated HPLC procedure with a lower limitof detection of 10 ng/ml.

[0132] The profile of blood plasma concentration of celecoxib inpatients receiving the celecoxib dosage forms is shown for both dosageforms in FIG. 1. It will be noted that with the suspension, a bloodplasma concentration greater than 300 ng/ml was attained just 15 minutesafter administration, whereas with the commercial capsule it took over 2hours to reach this concentration. Absorption of celecoxib from thesuspension was therefore much faster than from the capsule formulation.Calculated T_(max) for the suspension was 0.88 hours (i.e., about 53minutes), compared to 3.86 hours for the capsule. C_(max) for thesuspension was 703 ng/ml, by comparison with 548 ng/ml for the capsule.Overall bioavailability, as measured by an integral function of bloodplasma concentration over 24 hours, i.e., area under the curve, orAUC₀₋₂₄h, was similar for the two formulations.

[0133] Average pain relief scores over the 12 hour period followingadministration of treatments 1-4 are shown in FIG. 2. It will be seenthat treatments 1-3 all gave lasting relief of pain by comparison withplacebo (treatment 4); indeed pain relief was still evident withtreatments 1-3 as much as 24 hours after administration (not shown inFIG. 2).

[0134] Progression of pain relief during the first two hours afteradministration is more clearly seen in FIG. 3. It will be seen that thecelecoxib 200 mg suspension (treatment 3) began to show improved painrelief over placebo (treatment 4) as early as 15 minutes afteradministration. The first clear sign that ibuprofen 400 mg capsule(treatment 2) was giving greater pain relief than placebo was seen 30minutes after administration, and the first clear sign that celecoxib200 mg capsule (treatment 1) was giving greater pain relief than placebowas seen 45 minutes after administration.

[0135] A mean pain relief score approaching 2 was first seen withcelecoxib suspension (treatment 3) at 30 minutes, with ibuprofen capsule(treatment 2) at 1 hour and with celecoxib capsule (treatment 1) at1.5-2 hours after administration. The pain relief score obtained withcelecoxib suspension was statistically significantly superior to thatobtained with ibuprofen capsule at all times up to and including 1 hourafter administration.

[0136] Median time to onset of analgesia as recorded by the patients was19 minutes for celecoxib suspension, 28 minutes for ibuprofen capsule,40 minutes for celecoxib capsule, and >24 hours for placebo.

[0137] The results of the study reported in this Example clearlydemonstrate that where rapid absorption of celecoxib, consistent withthe pharmacokinetic profile described herein, can be obtained throughformulation modification, surprisingly fast onset of analgesia ispossible with this drug, equaling or even surpassing that obtainablewith a standard formulation of ibuprofen.

Example 2

[0138] A celecoxib solution formulation, sf-1, was prepared having thecomposition shown in table 2. TABLE 2 Composition (mg/g) of celecoxibsolution formulation SF-1 Component SF-1 Celecoxib 200 Water USP 26 HPMC(E5) 38 Ethanol 113 PEG 400 271 PVP 47 Polysorbate 80 217 Tromethamin 26Oleic acid 61 Propyl gallate NF 1 Total 1000

[0139] One gram of formulation SF-1 was individually placed into each ofseveral hard gelatin capsules (Capsugel) to form Test Composition 1.

[0140] A celecoxib suspension for comparative purposes was prepared asfollows:

[0141] A. Tween™ 80, 5.0 g, was placed in a volumetric flask.

[0142] B. Ethanol was added (to 100 ml) to form a mixture and themixture was swirled to form a uniform solution.

[0143] C. A 5 ml aliquot of the uniform solution was transferred to afresh 100 ml bottle containing 200 mg celecoxib, to form a premix.

[0144] D. Apple juice, 75 ml, was added to the premix to form anintermediate celecoxib suspension.

[0145] E. The intermediate celecoxib suspension was left to stand for 5minutes, and was then shaken to form a celecoxib suspension forcomparative purposes.

[0146] Bioavailability parameters resulting from administration of TestComposition 1, in comparison with the above-described comparativecelecoxib suspension and with a commercial celecoxib (Celebrex® ofPharmacia) 200 mg capsule, to human subjects were evaluated in a24-subject, randomized, four period, balanced, crossover study. Studyduration was approximately 15 days and subjects were randomly given oneof each of the four dosage forms on days 1, 5, 9 and 12; administrationof each dose was preceded by an 8 hour fasting period and wasaccompanied by 180 ml of water. Plasma blood levels for each subjectwere measured at pre-dose and at 15, 30, 45 minutes and 1, 1.5, 2, 3, 4,6, 8, 12 and 24 hours after dosage administration. C_(max) and AUC werecalculated from the data in accordance with standard procedure in theart. As shown in FIG. 4, ingestion of Test Composition 1 resulted in aC_(max) more than 2.5 times greater than resulted from ingestion of thecomparative celecoxib suspension or the commercial celecoxib capsule.Ingestion of Test Composition 1 also resulted in an AUC 43% greaterthan, and a T_(max) substantially similar to, that resulting fromingestion of the comparative celecoxib suspension.

Example 3

[0147] Two celecoxib/caffeine suspensions were prepared by the processdescribed below.

[0148] 1. PVP (K30) was added to water to form a PVP solution of 11.25mg PVP/ml solution; 12 ml of the PVP solution were drawn in duplicateand placed into each of two vessels (A and B).

[0149] 2. A 180 mg aliquot of caffeine was added to vessel A and a 900mg aliquot of caffeine was added to vessel B to form caffeinesuspensions A and B, respectively; both caffeine suspensions weresonicated as necessary.

[0150] 3. A celecoxib suspension (in water) was prepared comprising 30%celecoxib and PVP (K30) at a concentration of 11.25 mg PVP/ml solution;the celecoxib suspension was wet milled using a Dynomill to form amilled celecoxib suspension.

[0151] 4. Six ml of the milled celecoxib suspension were drawn induplicate and were individually added to each of caffeine suspensions Aand B to form celecoxib/caffeine suspensions A and B, respectively.

Example 4

[0152] Two solid celecoxib/caffeine compositions were prepared by theprocess described below.

[0153] 1. Fifteen ml each of celecoxib/caffeine suspension A and B ofExample 3 were drawn and placed into separate empty vessels.

[0154] 2. Lactose (1.5 g) and 15 mg of sodium lauryl sulfate were addedto each vessel with stirring to form intermediate suspensions A and B,respectively.

[0155] 3. Intermediate suspensions A and B were individually spray driedusing an apparatus consisting of an airbrush spray gun with-anatomizing-air supply system set at 10 PSI, according to the followingprocedure.

[0156] (a) The spray gun was positioned approximately six inches from aglass plate.

[0157] (b) Heated dry air (from a heat gun) was supplied to the surfaceof the glass plate to obtain a resulting plate temperature of about39-41° C.

[0158] (c) Fifteen ml of an intermediate suspension was delivered to thespray gun at a rate of 0.4-1.0 g/minute using a constant flow syringepump;

[0159] (d) Solid celecoxib/caffeine composition was collected on theglass plate and was then removed with a single edged razor blade andcollected in a vial.

Example 5

[0160] Two celecoxib/caffeine suspensions were prepared by the processdescribed below.

[0161] 1. PVP (K30) was added to water to form a PVP solution of 11.25mg PVP/ml solution; 12 ml of the PVP solution were drawn in duplicateand placed into each of two vessels (A and B).

[0162] 2. A 180 mg aliquot of caffeine was added to vessel A and a 900mg aliquot of caffeine was added to vessel B to form caffeinesuspensions A and B, respectively; both caffeine suspensions weresonicated as necessary.

[0163] 3. A celecoxib suspension (in water) was prepared comprising 30%celecoxib and PVP (K30) at a concentration of 11.25 mg PVP/ml solution;the celecoxib suspension was wet milled using a Dynomill to form amilled celecoxib suspension.

[0164] 4. Six ml of the milled celecoxib suspension were drawn induplicate and were individually added to each of caffeine suspensions Aand B to form celecoxib/caffeine suspensions A and B, respectively.

Example 6

[0165] Two solid celecoxib/caffeine compositions were prepared by theprocess described below.

[0166] 1. Fifteen ml each of celecoxib/caffeine suspension A and B ofExample 5 were drawn and placed into separate empty vessels.

[0167] 2. Lactose (1.5 g) and 15 mg of sodium lauryl sulfate were addedto each vessel with stirring to form intermediate suspensions A and B,respectively.

[0168] 3. Intermediate suspensions A and B were individually spray driedusing an apparatus consisting of an airbrush spray gun with anatomizing-air supply system set at 10 PSI, according to the followingprocedure.

[0169] (a) The spray gun was positioned approximately six inches from aglass plate.

[0170] (b) Heated dry air (from a heat gun) was supplied to the surfaceof the glass plate to obtain a resulting plate temperature of about39-41° C.

[0171] (c) Fifteen ml of an intermediate suspension was delivered to thespray gun at a rate of 0.4-1.0 g/minute using a constant flow syringepump;

[0172] (d) Solid celecoxib/caffeine composition was collected on theglass plate and was then removed with a single edged razor blade andcollected in a vial.

What is claimed is:
 1. A therapeutic method comprising orallyadministering to a mammalian subject in need of analgesia an effectivepain-relieving amount of a composition comprising celecoxib formulatedin such a way as to provide, when tested in fasting humans in accordancewith standard pharmacokinetic practice, a blood plasma concentrationprofile of celecoxib in which a concentration of at least about 250ng/ml is attained not later than about 30 minutes after oraladministration.
 2. The method of claim 1 wherein the composition isadministered in an amount providing about 50 to about 400 mg celecoxib.3. The method of claim 2 wherein the composition is administered in anamount providing about 100 to about 275 mg celecoxib.
 4. The method ofclaim 1 wherein the mammalian subject is a human subject.
 5. The methodof claim 1 wherein a plasma concentration of celecoxib of at least about300 ng/ml is attained not later than about 30 minutes after oraladministration.
 6. The method of claim 5 wherein a plasma concentrationof celecoxib of at least about 400 ng/ml is attained not later thanabout 30 minutes after oral administration.
 7. The method of claim 1wherein a plasma concentration of celecoxib of at least about 250 ng/mlis attained not later than about 15 minutes after oral administration.8. The method of claim 7 wherein a plasma concentration of celecoxib ofat least about 300 ng/ml is attained not later than about 15 minutesafter oral administration.
 9. The method of claim 1 wherein thecelecoxib is formulated such that it exhibits a T_(max) not greater thanabout 1.25 hours.
 10. The method of claim 9 wherein the celecoxib isformulated such that it exhibits a T_(max) not greater than about 1hour.
 11. The method of claim 1 wherein the celecoxib is formulated suchthat it exhibits a T_(max) not greater than about 50% of the T_(max)exhibited by a standard commercial formulation of celecoxib.
 12. Themethod of claim 11 wherein the celecoxib is formulated such that itexhibits a T_(max) not greater than about 33% of the T_(max) exhibitedby a standard commercial formulation of celecoxib.
 13. The method ofclaim 2 wherein the celecoxib is formulated such that it exhibits aT_(max) not greater than about 25% of the T_(max) exhibited by astandard commercial formulation of celecoxib.
 14. The method of claim 1wherein the celecoxib is formulated as an ultra-fine dispersion orsolution in a liquid medium.
 15. The method of claim 1 wherein thecelecoxib is formulated as solid particles having a D₉₀ particle size ofless than about 10 μm.
 16. The method of claim 15 wherein the celecoxibis formulated as solid particles having a D₉₀ particle size of less thanabout 2 μm.
 17. The method of claim 16 wherein the celecoxib isformulated as solid particles having a D₉₀ particle size of less thanabout 1 μm.
 18. The method of claim 1 wherein the celecoxib isformulated as solid particles having a weight average particle size ofabout 100 nm to about 800 nm.
 19. The method of claim 18 wherein thecelecoxib is formulated as solid particles having a weight averageparticle size of about 150 nm to about 600 nm.
 20. The method of claim19 wherein the celecoxib is formulated as solid particles having aweight average particle size of about 200 nm to about 400 nm.
 21. Themethod of claim 1 wherein the celecoxib is formulated as solid particleshaving a D₂₅ particle size of about 450 nm to about 1000 nm.
 22. Themethod of claim 1 wherein the celecoxib is formulated as solid particleswherein about 25% to 100% by weight of the solid particles have aparticle size of about 450 nm to about 1000 nm.
 23. The method of claim1 wherein the celecoxib is formulated as solid particles having a weightaverage particle size of about 450 nm to about 1000 nm. 24 The method ofclaim 1 wherein the celecoxib is formulated by dissolving the celecoxibin a suitable solvent and adding the resulting solution to an aqueousliquid to form a fine suspension, and wherein the suspension isadministered to the subject not more than about 15 minutes afterpreparation.
 25. The method of claim 1 wherein the celecoxib isformulated in solution in a pharmaceutically acceptable solvent.
 26. Themethod of claim 25 wherein the solvent is polyethylene glycol.
 27. Themethod of claim 25 wherein the celecoxib formulation is encapsulated asa unit dosage form having a capsule wall.
 28. The method of claim 27wherein the wall comprises gelatin.
 29. The method of claim 27 whereinthe wall comprises hydroxypropylmethylcellulose.
 30. The method of claim1 that comprises combination therapy with one or more drugs selectedfrom opioids and other analgesics.
 31. The method of claim 1 thatcomprises combination therapy with an opioid compound selected fromcodeine, meperidine, morphine and derivatives thereof.
 32. The method ofclaim 1 wherein the subject suffers from headache or migraine andwherein there is further orally administered to the subject avasomodulator, the celecoxib composition and the vasomodulator beingadministered in total and relative amounts effective to relieve pain inthe headache or migraine.
 33. The method of claim 32 wherein thevasomodulator is coformulated with the celecoxib composition.
 34. Themethod of claim 1 wherein the subject suffers from headache or migraineand wherein there is further orally administered to the subject analkylxanthine compound, the celecoxib composition and the alkylxanthinecompound being administered in total and relative amounts effective torelieve pain in the headache or migraine.
 35. The method of claim 34wherein the alkylxanthine compound is coformulated with the celecoxibcomposition.
 36. The method of claim 34 wherein the alkylxanthinecompound is selected from caffeine, theophylline and theobromine. 37.The method of claim 36 wherein the alkylxanthine compound is caffeine38. A therapeutic method for rapid pain relief in a mammalian subject inneed thereof, the method comprising orally administering to the subject,a composition comprising celecoxib in a formulation which provides aneffective pain-relieving plasma concentration of at least about 250ng/ml not later than about 30 minutes after oral administration.
 39. Themethod of claim 38 wherein the composition is administered in an amountproviding about 50 to about 400 mg celecoxib.
 40. The method of claim 39wherein the composition is administered in an amount providing about 100to about 275 mg celecoxib.
 41. The method of claim 38 wherein themammalian subject is a human subject.
 42. The method of claim 38 whereina plasma concentration of celecoxib of at least about 300 ng/ml isattained not later than about 30 minutes after oral administration. 43.The method of claim 42 wherein a plasma concentration of celecoxib of atleast about 400 ng/ml is attained not later than about 30 minutes afteroral administration.
 44. The method of claim 38 wherein a plasmaconcentration of celecoxib of at least about 250 ng/ml is attained notlater than about 15 minutes after oral administration.
 45. The method ofclaim 44 wherein a plasma concentration of celecoxib of at least about300 ng/ml is attained not later than about 15 minutes after oraladministration.
 46. The method of claim 38 wherein the celecoxib isformulated such that it exhibits a T_(max) not greater than about 1.25hours.
 47. The method of claim 46 wherein the celecoxib is formulatedsuch that it exhibits a T_(max) not greater than about 1 hour.
 48. Themethod of claim 38 wherein the celecoxib is formulated such that itexhibits a T_(max) not greater than about 50% of the T_(max) exhibitedby a standard commercial formulation of celecoxib.
 49. The method ofclaim 48 wherein the celecoxib is formulated such that it exhibits aT_(max) not greater than about 33% of the T_(max) exhibited by astandard commercial formulation of celecoxib.
 50. The method of claim 49wherein the celecoxib is formulated such that it exhibits a T_(max) notgreater than about 25% of the T_(max) exhibited by a standard commercialformulation of celecoxib.
 51. The method of claim 38 wherein thecelecoxib is formulated as an ultra-fine dispersion or solution in aliquid medium.
 52. The method of claim 38 wherein the celecoxib isformulated as solid particles having a D₉₀ particle size of less thanabout 10 μm.
 53. The method of claim 52 wherein the celecoxib isformulated as solid particles having a D₉₀ particle size of less thanabout 2 μm.
 54. The method of claim 53 wherein the celecoxib isformulated as solid particles having a D₉₀ particle size of less thanabout 1 μm.
 55. The method of claim 38 wherein the celecoxib isformulated as solid particles having a weight average particle size ofabout 100 nm to about 800 nm.
 56. The method of claim 55 wherein thecelecoxib is formulated as solid particles having a weight averageparticle size of about 150 nm to about 600 nm.
 57. The method of claim56 wherein the celecoxib is formulated as solid particles having aweight average particle size of about 200 nm to about 400 nm.
 58. Themethod of claim 38 wherein the celecoxib is formulated as solidparticles having a D₂₅ particle size of about 450 nm to about 1000 nm.59. The method of claim 38 wherein the celecoxib is formulated as solidparticles wherein about 25% to 100% by weight of the solid particleshave a particle size of about 450 nm to about 1000 nm.
 60. The method ofclaim 38 wherein the celecoxib is formulated as solid particles having aweight average particle size of about 450 nm to about 1000 nm.
 61. Themethod of claim 38 wherein the celecoxib is formulated by dissolving thecelecoxib in a suitable solvent and adding the resulting solution to anaqueous liquid to form a fine suspension, and wherein the suspension isadministered to the subject not more than about 15 minutes afterpreparation.
 62. The method of claim 38 wherein the celecoxib isformulated in solution in a pharmaceutically acceptable solvent.
 63. Themethod of claim 62 wherein the solvent is polyethylene glycol.
 64. Themethod of claim 62 wherein the celecoxib formulation is encapsulated asa unit dosage form having a capsule wall.
 65. The method of claim 64wherein the wall comprises gelatin.
 66. The method of claim 64 whereinthe wall comprises hydroxypropylmethylcellulose.
 67. The method of claim38 that comprises combination therapy with one or more drugs selectedfrom opioids and other analgesics.
 68. The method of claim 38 thatcomprises combination therapy with an opioid compound selected fromcodeine, meperidine, morphine and derivatives thereof.
 69. The method ofclaim 38 wherein the subject suffers from headache or migraine andwherein there is further orally administered to the subject avasomodulator, the celecoxib composition and the vasomodulator beingadministered in total and relative amounts effective to relieve pain inthe headache or migraine.
 70. The method of claim 69 wherein thevasomodulator is coformulated with the celecoxib composition.
 71. Themethod of claim 38 wherein the subject suffers from headache or migraineand wherein there is further orally administered to the subject analkylxanthine compound, the celecoxib composition and the alkylxanthinecompound being administered in total and relative amounts effective torelieve pain in the headache or migraine.
 72. The method of claim 71wherein the alkylxanthine compound is coformulated with the celecoxibcomposition.
 73. The method of claim 71 wherein the alkylxanthinecompound is selected from caffeine, theophylline and theobromine. 74.The method of claim 73 wherein the alkylxanthine compound is caffeine75. A therapeutic method for analgesia in a mammalian subject in needthereof, the method comprising orally administering to the subject, acomposition comprising celecoxib in a formulation which providesdetectable pain relief not later than about 30 minutes after oraladministration.
 76. The method of claim 75 wherein the composition isadministered in an amount providing about 50 to about 400 mg celecoxib.77. The method of claim 75 wherein the composition is administered in anamount providing about 100 to about 275 mg celecoxib.
 78. The method ofclaim 75 wherein the mammalian subject is a human subject.
 79. Themethod of claim 75 wherein a plasma concentration of celecoxib of atleast about 300 ng/ml is attained not later than about 30 minutes afteroral administration.
 80. The method of claim 75 wherein a plasmaconcentration of celecoxib of at least about 400 ng/ml is attained notlater than about 30 minutes after oral administration.
 81. The method ofclaim 81 wherein a plasma concentration of celecoxib of at least about250 ng/ml is attained not later than about 15 minutes after oraladministration.
 82. The method of claim 75 wherein a plasmaconcentration of celecoxib of at least about 300 ng/ml is attained notlater than about 15 minutes after oral administration.
 83. The method ofclaim 83 wherein the celecoxib is formulated such that it exhibits aT_(max) not greater than about 1.25 hours.
 84. The method of claim 75wherein the celecoxib is formulated such that it exhibits a T_(max) notgreater than about 1 hour.
 85. The method of claim 75 wherein thecelecoxib is formulated such that it exhibits a T_(max) not greater thanabout 50% of the T_(max) exhibited by a standard commercial formulationof celecoxib.
 86. The method of claim 75 wherein the celecoxib isformulated such that it exhibits a T_(max) not greater than about 33% ofthe T_(max) exhibited by a standard commercial formulation of celecoxib.87. The method of claim 86 wherein the celecoxib is formulated such thatit exhibits a T_(max) not greater than about 25% of the T_(max)exhibited by a standard commercial formulation of celecoxib.
 88. Themethod of claim 75 wherein the celecoxib is formulated as an ultra-finedispersion or solution in a liquid medium.
 89. The method of claim 75wherein the celecoxib is formulated as solid particles having a D₉₀particle size of less than about 10 μm.
 90. The method of claim 89wherein the celecoxib is formulated as solid particles having a D₉₀particle size of less than about 2 μm.
 91. The method of claim 90wherein the celecoxib is formulated as solid particles having a D₉₀particle size of less than about 1 μm.
 92. The method of claim 75wherein the celecoxib is formulated as solid particles having a weightaverage particle size of about 100 nm to about 800 nm.
 93. The method ofclaim 92 wherein the celecoxib is formulated as solid particles having aweight average particle size of about 150 nm to about 600 nm.
 94. Themethod of claim 75 wherein the celecoxib is formulated as solidparticles having a weight average particle size of about 200 nm to about400 nm.
 95. The method of claim 75 wherein the celecoxib is formulatedas solid particles having a D₂₅ particle size of about 450 nm to about1000 nm.
 96. The method of claim 75 wherein the celecoxib is formulatedas solid particles wherein about 25% to 100% by weight of the solidparticles have a particle size of about 450 nm to about 1000 nm.
 97. Themethod of claim 75 wherein the celecoxib is formulated as solidparticles having a weight average particle size of about 450 nm to about1000 nm.
 98. The method of claim 75 wherein the celecoxib is formulatedby dissolving the celecoxib in a suitable solvent and adding theresulting solution to an aqueous liquid to form a fine suspension, andwherein the suspension is administered to the subject not more thanabout 15 minutes after preparation.
 99. The method of claim 75 whereinthe celecoxib is formulated in solution in a pharmaceutically acceptablesolvent.
 100. The method of claim 99 wherein the solvent is polyethyleneglycol.
 101. The method of claim 99 wherein the celecoxib formulation isencapsulated as a unit dosage form having a capsule wall.
 102. Themethod of claim 101 wherein the wall comprises gelatin.
 103. The methodof claim 101 wherein the wall comprises hydroxypropylmethylcellulose.104. The method of claim 75 that comprises combination therapy with oneor more drugs selected from opioids and other analgesics.
 105. Themethod of claim 75 that comprises combination therapy with an opioidcompound selected from codeine, meperidine, morphine and derivativesthereof.
 106. The method of claim 75 wherein the subject suffers fromheadache or migraine and wherein there is further orally administered tothe subject a vasomodulator, the celecoxib composition and thevasomodulator being administered in total and relative amounts effectiveto relieve pain in the headache or migraine.
 107. The method of claim106 wherein the vasomodulator is coformulated with the celecoxibcomposition.
 108. The method of claim 75 wherein the subject suffersfrom headache or migraine and wherein there is further orallyadministered to the subject an alkylxanthine compound, the celecoxibcomposition and the alkylxanthine compound being administered in totaland relative amounts effective to relieve pain in the headache ormigraine.
 109. The method of claim 108 wherein the alkylxanthinecompound is coformulated with the celecoxib composition.
 110. The methodof claim 108 wherein the akylxanthine compound is selected fromcaffeine, theophylline and theobromine.
 111. The method of claim 110wherein the alkylxanthine compound is caffeine.
 112. The method of claim75 wherein the celecoxib formulation provides detectable pain relief notlater than about 15 minutes after oral administration
 113. A method ofuse of celecoxib, formulated in such a way as to provide, when tested inan effective pain-relieving amount in fasting humans in accordance withstandard pharmacokinetic practice, a blood plasma concentration profileof celecoxib in which a concentration of about 250 ng/ml is attained notlater than about 30 minutes after oral administration, in preparation ofa medicament for rapid relief of pain.
 114. A pharmaceutical compositioncomprising a formulation of solid particulate celecoxib having a weightaverage particle size of about 100 nm to about 800 nm.
 115. Acomposition for orally administering to a mammalian subject in need ofanalgesia, the composition comprising an effective pain-relieving amountof celecoxib formulated in such a way as to provide, when tested infasting humans in accordance with standard pharmacokinetic practice, ablood plasma concentration profile of celecoxib in which a concentrationof at least about 250 ng/ml is attained not later than about 30 minutesafter oral administration.
 116. A composition for rapid pain relief in amammalian subject in need thereof, the composition comprising celecoxibin an oral formulation which provides an effective pain-relieving plasmaconcentration of at least about 250 ng/ml not later than about 30minutes after oral administration.
 117. A composition for analgesia in amammalian subject in need thereof, the composition comprising an oralformulation which provides detectable pain relief not later than about30 minutes after oral administration.
 118. The composition of claim 117wherein the celecoxib formulation provides detectable pain relief notlater than about 15 minutes after oral administration.